Instrument for marking molding cutters or bits



April 14, 1925. 1,533,750

H. J. MITCHELL INSTRUMENT FOR MARKING MOLDINfi ,CUTTERS OR BITS FiledOct. 15, 1921 E3: g. .L

, I 4 I BY I 54 \DD-K MTG/WU Patent-eel Apr. 14 1925s rsaavseI-IABRIESON J- MITCHELL, OF SEATTLE, WASHINGTON, ASSIGNQB TC WILLIAM H,.PAY'NE, Q1? SEATTLE, WASHINGTON.

INSTRUMENT FOR MARKING MOLDING CUTTERS B 18-11%.

Application. filed. Gctobcr s, 1921. Serial no. 507,499.

To all whom it may concern:

Be it known that I, Hannrson J. TiTITCHELL, a citizen of the UnitedStates, residing at Seattle, in the county of King and State oflVashington, have invented certain new and useful Improvements inInstruments for lllarking Molding Cutters or Bits, of which thefollowing is a specification. i i V This invention relates toinstruments for marking uponcutter bits or the like lines to which theyare to be ground or sharpened for producing predetermined shapes ofmoldings or similar articles on a planing machine.

Difiiculty has hitherto been experienced in accurately marking outcutters of this character to a sharpening line which will afford apredetermined transverse shape by reason of the cutters being revolublymounted on cutter'heads in angular relations with respect to planesradial thereto. In order, therefore, to mark a blank for a cutter bitwhich will produce a molding having a selected curved or irregularoutline it is essential that the contour or design of such outline onthe blank be protracted longitudinally of thesame.

The object of the present invention is the provision of a device forquickly and ac. curately describing upon cutter bits grinding lines ofsuitable curvature and proportions for accomplishing the function abovereferred to.

The invention consists, generally, of a manually operated instrumenthaving a travelling trammel-beam which carries by one of its arms a bitmarking stylus whose movements are controlled by means of a tracingpoint carried by its other arm co-v operating with a pattern having ashape similar to the transverse section of the article which thefinished cutter bit is intended to produce.

The invention further consists in the novel construction, adaptation andcombination of parts hereinafter described and claimed. i

In the accompanying drawings,-

Figure 1 is a plan view of an instrument embodying my invention. Fig. 2is a front elevation of the same. Fig. 3 is an end elevation taken atthe right hand side of Figs. 1 and 2.. Fig. t is a sectional viewthrough, 4-.-4 of Fig. 2. Fig 5 is an end elevation of a type of cutterhead commonly used in wood planing machines. Fig. 6 is a perspectiveview of a work positioning plate, shown detached.

The invention'comprises a rigid frame which, as shown in the drawings,includes a base member or table 10 provided with a plane upper surface11 and having at each of its ends an upwardly extending standard or post12. Also included in said frame is a horizontal bar 13, preferablycircular, disposed longitudinally of the frame and is engaged in bracketpieces 14 which are respectively secured to said posts and bar, as

by means of set screws 15 and 16. Mounted for longitudinal and rotarymovements on the frame bar '13 is a relatively long sleeve 17 to whichis'rigidly secured a forwardly directed arm 18 and together constitutewhat will hereinafter be designated as the carriage. Swiveled'by meansof a pin 19 to the carriagearm 18 for horizontal rotary movements is ayoke 19 having an aperture 20, Fig. 1, to receive a horizontallydisposed trammel beam 21.

As illustrated saidyoke is provided with a horizontal slot 22 whichextends from an end thereof to beyond the aperture to affordbifurcations which serve through the medium-of a screw 23 to clamp saidyoke to the beam 21. Said slot alsofurnishes a way for a spline 24provided in the beam to obviate any rotary movement, of the latter withrespect to the yoke.

Adjustably secured, as by screws 25 and 26, to the beam at oppositesides of said yoke are attachments ,27 and 28, The attachment 27 isprovided with. a socket for a vertical rod or tracer 29 having a sharplower extremity. The other attachment, 28, is pro vided with avertically disposed screw threadedhole within which isenga-ged an.exte'riorlythreaded tubular holder 30 for a pencil or stylus 80 saidholder being provided with a head 31 to facilitate the ad justment ofthe same. I p

The lower end of said holder is desirably slotted so as to be broughtinto clamping relations with :the stylus by means of a'nut 32 having atapered aperture.

The table 10 is provided with a longitudinal groove 33 for the receptionof a plate 34: having a serrated edge 35 protruding above. the plane ofthe table to engage in transversely arranged corrugations 36, Fi

ployed in theframe groove 38 to serve as: a-

baclcing for positioning apatt'ern', as L3 f r example, upon thetableaudupon which, the pattern is held; by means of a spring blade 38 'which isconnected tothe'adj cent frame post-through the medium of a bracket rod39 ,-bl'ock 4O and screw 41 In Fig. 5, I show a cutter head of anordinary type'to' illustrate the relations of the bits 3?? which arecarried thereby with respect to the aXisof theliead spindle.-

In operation, the work or hit and the pattern 43 are placed upon thefram'eto have the stylusand tracing elements, when in vertical position,register therewith. The tran'iniel is tiltabl'y movable about the axisof tlie'bar 13 and, for convenience in setting,

' the sleeve 17 of the carriage is provided on its pe 'i'phery with anindex mark 51'to register'with agui'de line 50 on the ba 13when thecarriage i's'iirpositio'n-to retain the stylus and tracingpeintvertical. The yoke 19 is then temporarily disengaged from the train-Iss1 bea'in a' the carriage shifted, if necessary, to have the beamarms-of lengths, pro n'a'l-ly of each other, to suitthe angularrelations'at" which the cutterbit' is to be as plied to head Withrespect to a plane radial of the hee s is; p

The" beam is advantageously provided with angle indicating marl'ts 47,Fig. 1, to facilitate such adjustments of the beam with respect to the'oke,

Vith the" beam thus arranged, the operator} causes the tracing point: tofollow the outline, as of; of th'e pa'ttern' aSthereby influencingthebeam and carriage to carry the stylus upon the bit to n'i'arl;thesame, as at The travel ofthe' carriage produces similar movements ofthe tracer and stylus longitudinally of the mstru'ment; and the pivotalconnection of theyoke to'the carcarriage arranged for movementslongitmlinally of said frame, a trammel beam pivotally connectedintermediate its length to said carriage for movements parallel and inangular relations with respect to the direction of the carriage travel,a. stylus carried by one arm of said beam, and a pattern tracing pointcarried by the other arm of the beam.

2. In an instrument of the character de scribed, he combination with aframe having a table member, and a horizontal bar element'- in spacedrelations above said table, of a carriage mounted on the frame bar totravel longitudinally of the frame, yoke connected for rotation about avertical anisto said carriage, a rod extending horizontally through saidyoke, means provided on the yoke for securing the rod thereto at selected adjustmentslongitudinally of the rod and with respect to its axisof its rotation, a tracing point carried by the rod adjacentto one endthereof, and astylus carried by I therod adjacent to its other end.

3. In' an instrument of the character deseribed,'the combination with aframe having a table member provided with a' slot longitudinal thereof,said frame including a horizontal bar element in spaced relations abovesaid table, of carriage mounted on thefraine bar totrarel longitudinallyof the frame, a yoke pivotally connected to said carriage, a rodextending horizontally through said yoke, a tracing point carried by therod adjacent to one end thereof,- a stylus carried by the rodadjacent toits other end, and means provided in said slot for po sit.ion'in'gv apattern and blank upon said table in operativerelations with respect tosaid tracing point and the stylus 1-2- In an instrument of the characterdescribed, the" combination with a frame having a table member and ahorizontal bar eie ment in spaced: relations above said table, of acarriage mounted on the frame bar to travel longitudinally of the frame,a yoke p-ivotal'ly connected to said carriage for hori zontat rotarymovements, a rod ettending horizontally through said yoke, means forsecuring therod to the yoke at sel rte-d ad justinents axially of therod, a tracing point carried the rod adjacent to one end there of, and astylus carried by the rod adjacent to its other end. i r

' 5. In an instrument of thecharacter described, the combinationqwith aframehav ing a table member provided with a slot longitudina-l thereof,of a carriage mounted on the frame to travellongitudinally thereof, ayoke pivotally connected to said carriage, a

rod extending horizontally through said yoke,meansprovided on the yohefor securing the rod theretoat selected adjustments axially .of therod,a tracing point carried by the rod adjacent to one end thereof, a

stylus carried by the rod adjacent to its other end, and means providedin said slot for positioning a pattern and a blank upon said table inoperative relations with respect to said tracing point and the stylus.

6. In an instrument of the character de scribed, the combination with aframe, a carriage mounted thereon for relative longitudinal travel, atrammel having a swivel connection intermediate its length to saidcarriage, said trammel having a tracing element at one end and a markingelement at its other end, said elements being disposed in relation tosaid pivotal connection to afford amplified movements of the markingelement with respect to the tracing element for movements transverse tothe travel of said carriage.

7. In an instrument of the character described, a support for a patternand the work, a frame, a carriage mounted upon said frame for movementlongitudinally of said support, a traminel bar having a swivelconnection to said carriage and adapted to be adjustably moved'endwisethereof, a workmarker connected to one end of said bar and apattern-tracer connected to the other end of the bar whereby the markerand tracer are caused to be carried with said carriage in the travel ofthe latter and are revoluble with the bar about the pivotal connectionof the latter with the carriage and independently of the carriage whenthe same is stationary,

Signed at Seattle, W ashington, this 29th day of September, 1921.

HARRISON J. MITCHELL. Htnesses V PIERRE BARNES, MARGARET G. SUPPLE.

